The present invention relates to a method and apparatus that are used by vehicle air system designers to predict air system performance in a motor vehicle. The method and apparatus also provide the air system designer with a recommendation for air system components to optimize air system performance for a particular vehicle and its expected vocation. The present invention is described herein with particular reference to vehicle air systems, but those of ordinary skill in the art will recognize that the invention has wider application and can be used to predict performance of air systems found in applications other than vehicles without departing from the overall scope and intent of the invention. It is intended that the method and apparatus of the present invention relate to both vehicle and non-vehicle air systems.
Heretofore, a designer of a vehicle air system has been forced to utilize experience, rules of thumb, past performance observations, and other information in the selection of vehicle air system components such as air compressors, air dryers, filters, and the like. Several developments have made this approach highly undesirable. Pneumatic component manufacturers have demanded that their components be supplied with cleaner and drier air to increase performance. Selection of sub-optimal compressors and dryers results in air that is too moist and/or dirty owing to a compressor duty cycle that is above a recommended threshold.
On the other hand, in an effort to ensure an ample supply of clean, dry compressed air, the vehicle air system designer may select an air compressor and drier combination that is overly capable for a given application. This, then, needlessly increases the cost and weight of the vehicle.
Also, modern vehicles are being equipped with an ever increasing number of pneumatic components, and some of these additional components demand especially large amounts of compressed air from the vehicle air system. Many designers are simply unfamiliar with these devices and the load that they can potentially exert on a vehicle air system.
Furthermore, conventional methods of selecting air system components for vehicles do not account for variations in use by identical vehicles, i.e., identical buses may have different air system requirements depending upon road conditions, driving conditions, climate, and other variables. Thus, while a designers selection of an air compressor and dryer combination may be appropriate for some potential applications of a vehicle, it may be inappropriate for other potential applications of the same vehicle.
In light of the foregoing specifically noted deficiencies and others associated with convention air system design, a need has been identified for a new and nonobvious method and apparatus for predicting vehicle air system performance and recommending air system components.